Method and apparatus for providing transcranial magnetic stimulation (TMS) to a patient

ABSTRACT

Apparatus for applying Transcranial Magnetic Stimulation (TMS) to a patient, the apparatus including a head mount for disposition on the head of a patient; and a plurality of magnet assemblies for releasable mounting on the head mount, wherein each of the magnet assemblies includes a magnet for selectively providing a rapidly changing magnetic field capable of inducing weak electric currents in the brain of a patient so as to modify the natural electrical activity of the brain of the patient; wherein the number of magnet assemblies mounted on the head mount, their individual positioning on the head mount, and their selective provision of a rapidly changing magnetic field is selected so as to allow the spatial, strength and temporal characteristics of the magnetic field to be custom tailored for each patient, whereby to provide patient-specific TMS therapy, to assist in diagnosis or to map out brain function in neuroscience research.

REFERENCE TO PENDING PRIOR PATENT APPLICATIONS

This patent application is a divisional of granted prior U.S. patent application Ser. No. 15/281,475, filed Sep. 30, 2016 by The Methodist Hospital and Cornell University for METHOD AND APPARATUS FOR PROVIDING TRANSCRANIAL MAGNETIC STIMULATION (TMS) TO A PATIENT and issued as U.S. Pat. No. 10,500,408 B2, which is a continuation of pending prior U.S. patent application Ser. No. 13/829,349, filed Mar. 14, 2013 by The Methodist Hospital and Cornell University for METHOD AND APPARATUS FOR PROVIDING TRANSCRANIAL MAGNETIC STIMULATION (TMS) TO A PATIENT, and issued as U.S. Pat. No. 9,456,784, each of which are hereby incorporated herein by reference.

FIELD OF THE DISCLOSURE

This invention relates to Transcranial Magnetic Stimulation (TMS) in general, and more particularly to novel methods and apparatus for providing transcranial magnetic stimulation to a patient.

BACKGROUND

Transcranial Magnetic Stimulation (TMS) is a non-invasive procedure in which magnetic stimulation is applied to the brain in order to modify the natural electrical activity of the brain, whereby to provide therapy to a patient, to assist in diagnosis or to map out brain function in neuroscience research. More particularly, TMS applies a rapidly changing magnetic field to the brain of a patient in order to induce weak electric currents in the brain of the patient through electromagnetic induction. These weak electric currents modify the natural electrical activity of the brain of the patient, whereby to provide therapy to the patient, to assist in diagnosis or to map out brain function in neuroscience research. TMS has been approved by the Food and Drug Administration (FDA) for treating depression. TMS is also currently being investigated in the management of various other neurological and psychiatric disorders, including stroke, migraines, Parkinson's disease, tinnitus, autism, schizophrenia, etc. TMS is also being used to study brain function in neuroscience research.

Conventional TMS apparatus generally comprises an electromagnetic coil which is fixed in position relative to the head of the patient. Since the magnetic field applied to the patient is a function of the configuration of the electromagnetic coil, the current passed through the electromagnetic coil, and the location of the electromagnetic coil relative to the patient, the fixed construction of conventional TMS apparatus significantly limits the character of the magnetic field which can be applied to the patient, and hence significantly limits the TMS therapy which can be provided to the patient. In addition, conventional TMS apparatus generally utilizes very high electric currents in the electromagnetic coil, which raises the risk of accidental injury to the patient through electric shocks, burns, seizures, etc.

The present invention addresses the foregoing problems associated with the prior art by providing an improved method and apparatus for providing Transcranial Magnetic Stimulation (TMS) to a patient. In addition, the present invention also provides additional advantages over conventional TMS, e.g., (a) it comprises a portable, wearable device that can be used outside of a medical or research facility, e.g., at home; (b) patients can self-administer a prescribed treatment regimen at home through handheld, or worn, wired or wireless electronic controllers; (c) it comprises multiple magnetic stimulators directable at multiple brain structures which can lead to better treatment, diagnostic testing or insight into brain function through its use in neuroscience research; (d) it comprises multiple magnetic stimulators directable at one and the same brain structure which can be more effective because they can induce current flow in multiple orientations; and (e) it comprises multiple magnetic stimulators which can aggregate their magnetic fields for more robust brain stimulation.

SUMMARY

The present invention provides a novel method and apparatus for providing Transcranial Magnetic Stimulation (TMS) to a patient. Among other things, the present invention comprises the provision and use of novel TMS apparatus which allows the spatial, strength and temporal characteristics of the magnetic field generated by the TMS apparatus to be custom tailored for each patient, whereby to provide patient-specific TMS therapy or diagnostic testing. It also affords greater flexibility in open-ended investigations of brain function in neuroscience research.

In one form of the invention, there is provided apparatus for applying Transcranial Magnetic Stimulation (TMS) to a patient, wherein the apparatus comprises:

a head mount for disposition on the head of a patient; and

a plurality of magnet assemblies for releasable mounting on the head mount, wherein each of the magnet assemblies comprises a magnet for selectively providing a rapidly changing magnetic field capable of inducing weak electric currents in the brain of a patient so as to modify the natural electrical activity of the brain of the patient;

wherein the number of magnet assemblies mounted on the head mount, their individual positioning on the head mount, and their selective provision of a rapidly changing magnetic field is selected so as to allow the spatial, strength and temporal characteristics of the magnetic field to be custom tailored for each patient, whereby to provide patient-specific TMS therapy or diagnostic testing, as well as greater flexibility in open-ended investigations of brain function in neuroscience research. In one preferred form of the invention, each of the magnet assemblies comprises a magnet for selectively providing a rapidly changing magnetic field of at least 500-600 Tesla/second corresponding to a magnet movement speed of no less than 400 Hertz.

In another form of the invention, there is provided a method for providing Transcranial Magnetic Stimulation (TMS) to a patient, the method comprising:

providing apparatus comprising:

a head mount for disposition on the head of a patient; and

a plurality of magnet assemblies for releasable mounting on the head mount, wherein each of the magnet assemblies comprises a magnet for selectively providing a rapidly changing magnetic field capable of inducing weak electric currents in the brain of a patient so as to modify the natural electrical activity of the brain of the patient;

positioning the head mount on the head of the patient, and positioning a selected number of magnet assemblies on the head mount at selected locations; and

selectively providing a rapidly changing magnetic field with at least one of the magnet assemblies;

wherein the number of magnet assemblies mounted on the head mount, their individual positioning on the head mount, and their selective provision of a rapidly changing magnetic field is selected so as to custom tailor the spatial, strength and temporal characteristics of the magnetic field for that patient, whereby to provide patient-specific TMS therapy or diagnostic testing, as well as greater flexibility in open-ended investigations of brain function in neuroscience research. In one preferred form of the invention, each of the magnet assemblies comprises a magnet for selectively providing a rapidly changing magnetic field of at least 500-600 Tesla/second corresponding to a magnet movement speed of no less than 400 Hertz.

In another form of the invention, there is provided apparatus for applying Transcranial Magnetic Stimulation (TMS) to a patient, wherein the apparatus comprises:

a head mount for disposition on the head of a patient; and

a plurality of magnet assemblies mounted on the head mount in a predetermined pattern, wherein each of the magnet assemblies comprises a magnet for selectively providing a rapidly changing magnetic field capable of inducing weak electric currents in the brain of a patient so as to modify the natural electrical activity of the brain of the patient;

wherein the number of magnet assemblies mounted on the head mount, their individual positioning on the head mount, and their selective provision of a rapidly changing magnetic field is selected so as to allow the spatial, strength and temporal characteristics of the magnetic field to be custom tailored for each patient, whereby to provide patient-specific TMS therapy, to assist in diagnosis or to map out brain function in neuroscience research. In one preferred form of the invention, each of the magnet assemblies comprises a magnet for selectively providing a rapidly changing magnetic field of at least 500-600 Tesla/second corresponding to a magnet movement speed of no less than 400 Hertz.

In another form of the invention, there is provided a method for providing Transcranial Magnetic Stimulation (TMS) to a patient, the method comprising:

providing apparatus comprising:

a head mount for disposition on the head of a patient; and

a plurality of magnet assemblies mounted on the head mount in a predetermined pattern, wherein each of the magnet assemblies comprises a magnet for selectively providing a rapidly changing magnetic field capable of inducing weak electric currents in the brain of a patient so as to modify the natural electrical activity of the brain of the patient;

positioning the head mount on the head of the patient; and

selectively providing a rapidly changing magnetic field with at least one of the magnet assemblies;

wherein the number of magnet assemblies mounted on the head mount, their individual positioning on the head mount, and their selective provision of a rapidly changing magnetic field is selected so as to custom tailor the spatial, strength and temporal characteristics of the magnetic field for that patient, whereby to provide patient-specific TMS therapy, to assist in diagnosis or to map out brain function in neuroscience research. In one preferred form of the invention, each of the magnet assemblies comprises a magnet for selectively providing a rapidly changing magnetic field of at least 500-600 Tesla/second corresponding to a magnet movement speed of no less than 400 Hertz.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other objects and features of the present invention will be more fully disclosed or rendered obvious by the following detailed description of the preferred embodiments of the invention, which is to be considered together with the accompanying drawings wherein like numbers refer to like parts, and further wherein:

FIGS. 1 and 2 are schematic views illustrating novel apparatus for providing Transcranial Magnetic Stimulation (TMS) to a patient;

FIG. 3 is a schematic view illustrating how selective ones of the magnet assemblies of the TMS apparatus of FIGS. 1 and 2 may be activated at selected times so as to provide the desired TMS therapy to a patient, diagnostic testing or investigative protocol in neuroscience research;

FIG. 4 is a schematic view illustrating the physics of magnetic stimulation in a conductor;

FIG. 5 is a schematic view illustrating the biophysics of magnetic stimulation of a brain;

FIG. 6 is a table illustrating some of the advantages of the present invention over conventional TMS; and

FIG. 7 is a schematic view illustrating alternative apparatus for providing TMS to a patient.

DETAILED DESCRIPTION

Looking first at FIGS. 1 and 2, there is shown novel Transcranial Magnetic Stimulation (TMS) apparatus 5 for providing TMS to a patient. Among other things, and as will hereinafter be discussed, novel TMS apparatus 5 allows the spatial, strength and temporal characteristics of the magnetic field generated by the TMS apparatus to be custom tailored for each patient, whereby to provide patient-specific TMS therapy, to assist in diagnosis or to map out brain function in neuroscience research.

More particularly, TMS apparatus 5 generally comprises a head mount 10 for positioning on the head of a patient, a plurality of magnet assemblies 15 which are releasably mounted to head mount 10, and a plurality of leads 20 for connecting each of the magnet assemblies 15 to a computerized controller 25. Computerized controller 25 may be a self-standing device or, if desired, computerized controller 25 may be wearable, e.g., on a waistband, an armband, etc. Additionally, if desired, magnet assemblies 15 may be connected to computerized controller 25 wirelessly, whereby to eliminate the need for leads 20.

In one preferred form of the invention, head mount 10 comprises a soft, form-fitting skull cap adapted to cover the head of the patient while leaving the face and ears of the patient exposed. Head mount 10 is intended to provide a stable support for the aforementioned magnet assemblies 15, and to that end head mount 10 preferably comprises a textile construct (e.g., woven, braided or knit fibers) that has a stable structure but which can breathe (for patient comfort). Alternatively, the head mount could be constructed of other materials such as soft plastic. Head mount 10 preferably includes a chin strap 30 so that the head mount can be fastened onto the head of a patient with light tension, whereby to ensure that the head mount maintains a fixed position on the head of the patient.

As noted above, a plurality of magnet assemblies 15 are releasably mounted to head mount 10. More particularly, magnet assemblies 15 are releasably mounted to head mount 10 so that the number of magnet assemblies 15, and/or their individual positioning on head mount 10, can be varied as desired by the clinician or investigator. To this end, head mount 10 preferably comprises a plurality of fastener bases 35 which are distributed about the outer surface of head mount 10, and each of the magnet assemblies 15 preferably comprises a counterpart fastener connect 40 adapted to mate with a fastener base 35, whereby to allow each magnet assembly 15 to be releasably secured to head mount 10 substantially anywhere about the surface of the head mount. It will be appreciated that, as a result of this construction, it is possible to releasably secure the desired number of magnet assemblies 15 to head mount 10, at the desired locations for those magnet assemblies 15, so that the number of magnet assemblies 15, and/or their positioning on head mount 10, can be varied as desired by the clinician or investigator.

By way of example but not limitation, head mount 10 may comprise a woven fabric skull cap covering the skull of the patient, the plurality of fastener bases 35 disposed on head mount 10 may each comprise one half of a conventional hook-and-loop (e.g., Velcro™) fastener, and the fastener connects 40 of the magnet assemblies 15 may each comprise the second half of a conventional hook-and-loop (e.g., Velcro™) fastener. In this way, each of the magnet assemblies 15 may be releasably fastened to a fastener base 35, and hence to head mount 10.

In one preferred form of the invention, magnet assemblies 15 each comprise a motor 45 and a permanent magnet 50. Permanent magnet 50 is mounted to the drive shaft 55 of motor 45, such that when motor 45 is energized, permanent magnet 50 will rotate, whereby to provide a rapidly changing magnetic field about the magnet assembly. In one preferred form of the invention, each of the magnet assemblies 15 comprises a permanent magnet 50 for selectively providing a rapidly changing magnetic field of at least 500-600 Tesla/second corresponding to a magnet movement speed of no less than 400 Hertz. As will be appreciated by those knowledgeable in the field of TMS, by applying this rapidly changing magnetic field of at least 500-600 Tesla/second, corresponding to magnet movement speed of no less than 400 Hertz, to the brain of a patient, weak electric currents can be induced in the neurons of the brain of the patient. These weak electric currents modify the natural electrical activity of the brain of the patient, whereby to provide therapy to the patient, to assist in diagnosis or to map out brain function in neuroscience research. In one preferred form of the invention, motor 45 is a variable speed motor, such that permanent magnet 50 may be rotated faster or slower, as desired, whereby to adjust the voltage of the electric currents induced in the neurons of the brain of the patient, as will hereinafter be discussed in further detail. In one preferred form of the invention, permanent magnet 50 comprises a rare earth magnet, e.g., a neodymium magnet.

TMS apparatus 5 also comprises a computerized controller 25 for independently controlling the operation of each of the magnet assemblies 15, i.e., turning motors 45 on or off, regulating the speeds of motor rotation, etc. Leads 20 connect computerized controller 25 to each of the magnet assemblies 15.

Thus, in accordance with the present invention, a clinician or investigator first determines, for each individual patient, (i) how many magnet assemblies 15 should be mounted to head mount 10, (ii) where those magnet assemblies 15 should be mounted on head mount 10, (iii) when various magnet assemblies 15 should have their permanent magnets 50 rotated, and (iv) the speed of such rotation, in order to precisely tailor the spatial, strength and temporal characteristics of the magnetic field which is generated by TMS apparatus 5, whereby to provide that patient with patient-specific TMS therapy, to assist in diagnosis or to map out brain function in neuroscience research. Thereafter, when TMS therapy or test is to be applied to the patient, the patient puts on head mount 10, the clinician or investigator mounts the appropriate number of magnet assemblies 15 to head mount 10, positioning those magnet assemblies at the appropriate locations on head mount 10, and then computerized controller 25 thereafter controls which magnet assemblies 15 have their magnets rotated when, and at what speed. In this way, the spatial, strength and temporal characteristics of the magnetic field generated by TMS apparatus 5 can be precisely tailored according to each patient's needs, whereby to provide patient-specific TMS therapy to the patient, to assist in diagnosis or to map out brain function in neuroscience research. See, for example, FIG. 3, which shows how selected magnet assemblies 15, located at various locations about head mount 10, may have their respective permanent magnets rotated at different times. In this respect it will be appreciated that as the permanent magnet of a particular magnetic assembly 15 is rotated, it will apply a rapidly changing magnetic field to the patient, and this changing magnetic field is a function of the size and strength of the permanent magnet 50 of that magnet assembly and the rate at which the permanent magnet is rotated. See also, for example, FIG. 4, which illustrates the physics of magnetic stimulation in a conductor, and FIG. 5, which illustrates the rapid voltage fluctuations induced by magnetic stimulation in a human brain. Furthermore, it will be appreciated that the rapidly changing magnetic fields produced by the plurality of magnetic assemblies 15 located on head mount 10 together aggregate into a complex, composite, rapidly changing magnetic field which varies across the brain of the patient, both spatially and temporally, according to the positions of the magnet assemblies 15 on head mount 10 and the relative timings of their respective magnet rotations.

Thus it will be seen that with the novel TMS apparatus 5 of the present invention, the clinician or investigator may custom tailor the spatial, strength and temporal characteristics of the magnetic field generated by the TMS apparatus 5 for each patient, whereby to provide patient-specific TMS therapy, to assist in diagnosis or to map out brain function in neuroscience research.

Significantly, the present invention comprises a portable, wearable device that can be used outside of a medical or research facility, e.g., at home. Furthermore, patients can self-administer a prescribed treatment regimen at home through handheld, or worn, wired or wireless electronic controllers.

It should be appreciated that, inasmuch as the present invention comprises multiple magnetic stimulators directable at multiple brain structures, it can be possible to achieve better treatment, diagnostic testing or insight into brain function through its use in neuroscience research.

Also, inasmuch as the present invention comprises multiple magnetic stimulators directable at a single brain structure, it can be possible to achieve superior results because they can induce current flow in multiple orientations.

Furthermore, inasmuch as the present invention comprises multiple magnetic stimulators which can aggregate their magnetic fields for more robust brain stimulation, it can be possible to achieve better treatment, diagnostic testing or insight into brain function through its use in neuroscience research. Among other things, this more robust brain stimulation can relate to which regions of the brain are stimulated, the orientation(s) of the current flow induced in the regions which are stimulated, the magnitudes of the current flow induced in the regions which are stimulated, and the timings of such stimulation.

In accordance with the present invention, there is also provided a novel method for determining how many magnet assemblies 15 should be mounted to head mount 10, where those magnet assemblies 15 should be mounted on head mount 10, when various magnet assemblies 15 should have their magnets rotated, and the speed of such magnet rotation, in order to precisely tailor the spatial, strength and temporal characteristics of the magnetic field which is to be applied to that patient, whereby to provide that patient with patient-specific TMS therapy, to assist in diagnosis or to map out brain function in neuroscience research. More particularly, in accordance with the present invention, head mount 10 may include a plurality of electrodes 60 for monitoring changes in the electrical activity of the brain of the patient. Electrodes 60 are preferably connected to computerized controller 25 so that changes in the electrical activity of the brain, monitored by electrodes 60, can be correlated with variations in the spatial, strength and temporal characteristics of the magnetic field being applied to the patient by TMS apparatus 5, which in turn corresponds to the number, location and speed of rotation of the various magnet assemblies 15. In this way, using a feedback process, changes in the number, location and speed of rotation of the various magnet assemblies 15 can be correlated to changes in the electrical activity of the brain of the patient, whereby to create a patient specific TMS therapy, to assist in diagnosis or to map out brain function in neuroscience research.

The present invention offers numerous advantages over the prior art. More particularly, the novel TMS apparatus 5 of the present invention allows the spatial, strength and temporal characteristics of the magnetic field to be custom tailored for each patient, whereby to provide patient-specific TMS therapy, to assist in diagnosis or to map out brain function in neuroscience research. Among other things, the present invention provides the following significant advantages over conventional TMS: (a) it comprises a portable, wearable device that can be used outside of a medical or research facility, e.g., at home; (b) patients can self-administer a prescribed treatment regimen at home through handheld, or worn, wired or wireless electronic controllers; (c) it comprises multiple magnetic stimulators directable at multiple brain structures which can lead to better treatment, diagnostic testing or insight into brain function through its use in neuroscience research; (d) it comprises multiple magnetic stimulators directable at one and the same brain structure which can be more effective because they can induce current flow in multiple orientations; and (e) it comprises multiple magnetic stimulators which can aggregate their magnetic fields for more robust brain stimulation. In addition, the present invention eliminates the risk of accidental injury to the patient through electric shocks, burns, seizures, etc.

See FIG. 6, which lists some of the advantages of the present invention over conventional TMS apparatus.

Modifications of the Preferred Embodiments

It should be appreciated that many additional changes in the details, materials, steps and arrangements of parts, which have been herein described and illustrated in order to explain the nature of the present invention, may be made by those skilled in the art while still remaining within the principles and scope of the invention.

By way of example but not limitation, the entire outer surface of head mount 10 may be covered by a single large fastener base 35, or major sections of head mount 10 may be covered by several large fastener bases 35, where the one or more large fastener bases 35 receive one or more magnet assemblies 15.

Furthermore, if desired, head mount 10 may be formed as a harness, comprising a plurality of straps which are connected together, but have spacing between the various straps, so as to provide a grid-like structure about the head. These straps can be formed out of leather, plastic, a textile, etc. In this form of the invention, fastener bases 35, and hence magnet assemblies 15, are mounted along the straps which make up head mount 10.

In addition, if desired, magnet assemblies 15 may be constructed so that magnets 50 are moved longitudinally, rather than rotationally, in order to produce a rapidly changing magnetic field. See, for example, FIG. 7, where solenoids 65 move magnets 50 rapidly so as to create the changing magnetic field utilized in the present invention.

Also, if desired, permanent magnets 50 may be replaced by small electromagnets, if the requisite high strength magnetic field can be achieved (e.g., so as to provide a rapid change of magnetic flux of at least 500-600 Tesla/second), and with the appropriate amount of cooling to prevent heating and melting of the magnet coils.

In accordance with the present invention, it is also possible to provide a head mount 10 (e.g., a skull cap) which has a predetermined number of magnet assemblies 15 already mounted on (or incorporated into) head mount 10 in a predetermined pattern. In this case, the clinician determines which ones of the predetermined, predisposed magnet assemblies 15 should be activated and, for those magnet assemblies which are to be activated, when they should have their magnets rotated, and the speed of such rotation, in order to precisely tailor the spatial, strength and temporal characteristics of the magnetic field which is to be applied to the patient, whereby to provide that patient with patient specific TMS therapy, to assist in diagnosis, or to map out brain function in neuroscience research. Furthermore, in this form of the invention, it may be desirable to provide a kit of such devices, wherein each device in the kit comprises a head mount 10 (e.g., a skull cap) which has a predetermined number of magnet assemblies 15 already mounted on (or incorporated into) head mount 10 in a predetermined pattern, with each device in the kit providing a different predetermined pattern of magnet assemblies 15.

These and other changes will be apparent to those skilled in the art in view of the present disclosure and are considered to be within the scope of the present invention. 

What is claimed is:
 1. An apparatus for applying Transcranial Magnetic Stimulation (TMS) to a patient, wherein the apparatus comprises: a head mount for disposition on the head of the patient; and a plurality of magnet assemblies mounted on the head mount in a predetermined pattern, wherein each of the magnet assemblies comprises a magnet for selectively providing a rapidly changing magnetic field of 500-5000 Tesla/second, corresponding to a magnet movement speed of no less than 400 Hertz, configured to induce electric currents in the brain of the patient so as to modify natural electrical activity of the brain of the patient; wherein the number of magnet assemblies mounted on the head mount, their individual positioning on the head mount, and their selective provision of the rapidly changing magnetic field is selected so as to allow the spatial, strength and temporal characteristics of the rapidly changing magnetic field to be custom tailored for the patient, whereby to provide patient-specific TMS therapy, to assist in diagnosis or to map out brain function in neuroscience research.
 2. The apparatus according to claim 1 comprising a kit of devices, wherein each device comprises a head mount having a plurality of magnet assemblies mounted on the head mount in a predetermined pattern, and further wherein each of the devices in the kit has its respective plurality of magnet assemblies mounted in a different predetermined pattern.
 3. The apparatus according to claim 1, wherein the magnet assemblies comprise a permanent magnet and apparatus for moving the permanent magnet.
 4. The apparatus according to claim 1, wherein the magnet assemblies comprise an electromagnet.
 5. A method for providing Transcranial Magnetic Stimulation (TMS) to a patient, the method comprising: providing an apparatus comprising: a head mount for disposition on the head of the patient; and a plurality of magnet assemblies mounted on the head mount in a predetermined pattern, wherein each of the magnet assemblies comprises a magnet for selectively providing a rapidly changing magnetic field of 500-5000 Tesla/second, corresponding to a magnet movement speed of no less than 400 Hertz, configured to induce electric currents in the brain of the patient so as to modify natural electrical activity of the brain of the patient; positioning the head mount on the head of the patient; and selectively providing the rapidly changing magnetic field with at least one of the magnet assemblies; wherein the number of magnet assemblies mounted on the head mount, their individual positioning on the head mount, and their selective provision of the rapidly changing magnetic field is selected so as to custom tailor the spatial, strength and temporal characteristics of the rapidly changing magnetic field for that patient, whereby to provide patient-specific TMS therapy, to assist in diagnosis or to map out brain function in neuroscience research.
 6. The method according to claim 5, wherein the magnet assemblies comprise a permanent magnet and apparatus for moving the permanent magnet.
 7. The method according to claim 1, wherein the magnet assemblies comprise an electromagnet. 